Drill press table operating means



July 5, 1938.. H. E. TAUTZ DRILL PRESS TABLE OPERATING MEANS Filed Aug.31, 1956 Patented July5, 1.938 g vmre f srA-res PATEN F C Herbert E.Tautz, Milwaukee,wis., assignor to gala Manufacturing .Company,Milwaukee,

' Application August 31, 1936, Serial No. 98,778 4 Claims. (Cl. 77-63)This invention relates to means for elevating tablesupported thereby andembodying features or depressing the tableof a drill press or similar ofmy, invention. means, said table being so mounted as to 136- Fig. 2 is aslightly modified form of the same. rotatable around the column of thedrill press. Rig. 3 is a section of the column and rack 5 It relatesparticularly to mechanism for raisshown in Fig. 2 on the plane indicatedby the 5 ing such tables gradually and also for preventline 3--3. ingthe said tables from falling down suddenly All the figures are more orless diagrammatic. if the clamping device should become loosened.Referring now to 1, there is shown a base More specifically, the deviceconsists of means 7 I. supporting a. column 2 to which a split collar 10comprising a rack, a pinion meshing therewith, 3 may be secured so as tobe vertically adjustable 10 and means for operating said pinion whichmay by any suitable means, such as the bolts 4.

. consist of a worm and worm gear, with a crank Upon the upper surface 5of the said collar or other device for actuating said worm, the rests athrust bearing 6 of any suitable type comrack being guidedinagrooveformed in the tableprising a lower bearing plate I, a plurality of IIsupporting bracket and the lower end of the balls 8, an upper bearingplate 9 and a protecting rack resting upon an anti-friction device whichcover III. This hearing may be of any suitable preferably is locatedaround the column of the type and while illustrated diagrammatically asdrill press. c r a ball bearing may, of course, also be made with It hasheretofore been proposed to provide rollers if preferred, as the'exactnature of the 90 means comprising a rack and pinion, together bearingdoes not form a part of th present 1 '20 with actuating means for suchpinion, to elevention.. I vate the table of a machine of this kind, butA rack bar II has its lower end it supported such devices wereunsuccessful except when the by the thrust bearing 6 by resting upon therack was made so short as to provide only a same and cooperates withapinion l3 secured on relatively small and, therefore, practically useacommon shaft M with a worm wheel [5 which 25 less. range of verticalmovement of the table, bein turn meshes with a worm l6 operativelycause, as I have now found, when the rack was mounted on the shaft I!carried by the bearing made long enough to be of real practical service,i8 of the housing i9, said shaft I! having a ball the friction producedat the lower end of' the crank 20 or other suitable manipulating. crankrack where it abutted against the face of the device mounted thereon asshown. 30

column was sufficient to bend the rack sufficiently The housing l9carries the table 2| which is out of its proper vertical position tocause it at secured to said housing by means'of the bolt 22 least tobind and make its operation by the pinand nut 23 so as to pivot aboutsaid bolt 22 ion impossible and often also to actually bend when the nut23 is loosened. In order to secure the rack out of shape, thuspermanently injurthe table 2i in its customary or normal position, 35ing the mechanism. which is with the plane of its top at right angles Ihave found the above mentioned friction to to the axis of the column 2,a suitable pin 24, be the reason for the faulty operation ofdeviceshaving a bent end for convenience of manipulaof this nature andhave-provided a remedy for tion, may be engaged in a hole25 formed inthe 40 the same by providing ananti-friction device lower flange 26 ofthe table and also in the hous- 40 for supporting the lower end of therack bar. ing is, so that when said pin is engaged in said Due to theusually heavy weight of the drill press hole the table 2| cannot turnabout the pivot table and the associated operating mechanism, '22, butwill automatically be maintained in its the pressure exerted by therack'bar upon its normal position.

support on the base of the column was excessive The housing i9 ispreferably longitudinally 45 and this caused the binding action aboveresplit in the customary way and is secured to the ferred to, and I haveremedied this defect by column 2 with the desired degree of tightness byproviding a thrust bearing to ease the friction, means of bolts and nuts21 which may be tightpreferably a ball or roller thrust bearing. ened tothe desired degree. A lever 28 having an I have disclosed a preferredembodiment of enlarged head 29 may cooperate with one of said 50 theinve in the P t Specification and bolts or. nuts 21 so as to affordrapid means for illustrated it in th mpanyin r wi g. manually tighteningor loosening'the table 2| wherein: with respect to the column 2.

Fig. i is a front elevation of a portion of the In Fig. 2 all the partsenumerated with respect base and column of a drill press, with thedrill. to Fig. 1 are also shown and designated by the 55 same referencecharacters with the exception that in this modified form the collar 3 isomitted and the thrust bearing 6 -ests directly upon the flat surface3|! formed at the top of the base The operation of the device will bereadily understood from the above description of its construction.

Referring first to the Fig. 1 form, the collar 3 will be adjustedmanually to any suitable desired height on the column'2 and clampedthere by the bolts and nuts 4. The housing l9 which carries the table 2|will then be brought to the desired degree of looseness about the column2 to permit the ready adjustment of the table 2| up and down along saidcolumn and also in a horizontal rotary manner around said column tocorrespond to the work being done by the drill press or other mechanismof which it forms a part at the time in question.

In order to adjust the table 2| to the prope height the ball crank 20will be turned manually in the proper direction to cause the worm l6 toturn the worm wheel I5 in the proper direction and to the proper extentto raise or lower the table 2 I, this being accomplished by means'of thepinion l3 and the rack II in engagement therewith. A

Having adjusted the table to the proper height in this manner it maythen be necessary to rotate' said table about the column 2 toproperlyaline the workpiece carried thereby at the time with the drill or othertool. This is accomplished by manually engaging the table 2| andshifting it to the desired position by turning it about the said column.

It will be obvious that because of the self-locking nature of the wormand worm wheel drive the table 2| will automatically remain in whateververtical position it has been placed, so that the table 2| cannot dropsuddenly if the bolts and nuts 21 are inadvertently left too loose, thusavoiding damage, particularly in the hands of inexperienced operators.

In previous constructions of this type there was great difflculty inmaking the rotary adjustment -because in such previous constructionsthere was no anti-friction device 6 provided atthe lower end of the rackbar II and the consequence was that because of the relatively greatweight of the housing l9 and the mechanism contained therein, togetherwith the machine table 2|, the lower end of the rack bar II was causedto bind or seize against its supporting means, thus producing sufficientfrictional force to make it practically impossible to turn the table 2|about the column without binding and in many cases without permanentlyinjuring the rack bar This has now been obviated by means of theanti-fric-v tion device 6 which avoids the development of any materialfrictional force resisting the movement of the lower end l2 of the rackbar II and thus automatically prevents any injury or binding.

It will be understood, of course, that the rack bar H is not secured inany way to either the housing IS, the column 2, or the bearing 6although if preferred no harm would be done by positively securing thelower end |2 to the upper movable portion of the bearing 6. The rackslides freely through the opening or keyway 3| provided in the housingI9. The rack bar is, therefore, readily removable or interchangeable forothers of diiferent length or a new one may be substituted readily for adefective or damaged one.

At the same time that the present'construction eliminates thepossibility of binding or injury it also materially decreases the manualeffort necessary to turn the table 2| about the'column 2 and thus hasseveral advantages.

When the table 2| has been brought to its final position of adjustmentit may, -of course, be held there by manipulating the lever 28 by meansof its knob 29 to tighten the corresponding bolt or nut 21 and thustightly hold the housing IS on the column 2.

In the Fig. 2 form, the operation and construction are, of course,identical'with those of Fig. ,l, except that since no adjustable collar3 is provided, use is made instead of theupper flat surface 3|! alreadypresent at the top of-the base I. The Fig. 1 form permits the use of asomewhat shorter rack bar than the Fig. 2 form and each form may bepreferred for some particular use.

Having described my invention and stated the advantages thereof it willbe obvious that it may be embodied also in other forms and it will,therefore, be understood that the invention is not to be limited to adrill press but may flnd employment in any other tool wherein it isnecessary to adjust a heavy table by vertical and rotary movementscombined, and the invention is, therefore, to be considered as limitedonly by the following claims.

I claim:

1. In a machine tool having a relatively stationary column and a tablesupported thereby, said table having a slot adjacent the column, meansrotatable around the column for adjusting said table vertically, saidmeans comprising a rack bar extending along saidlcolumn, and through theslot in said table, a pinion carried by said table and in mesh withtherack bar, and anti-friction means for supporting the lower end ofsaid rack bar, said anti-friction'means encircling the said column, saidrack bar being guided by the sides of the slot and having its lower endresting upon the anti-friction means, whereby the rack bar is freelyremovable from the machine tool in an upward direction.

2. In a machine tool having a relatively stationary column and a tablesupported thereby, means rotatable on the column for adjusting saidtable vertically, said means comprising a rack bar extending along saidcolumn, a pinion carried by the table and in mesh with the said rackbar, anti-friction means for supporting the lower end of said rack bar,said rack bar being freely removable in an upward direction, saidanti-friction means being arranged around the said column, a collaradjustable along said column for supporting said anti-friction means,and means for securing said collar in its adjusted position.

3; In a'machine tool having a relatively stationary column and a tablesupported thereby, means rotatable on the column for adjusting saidtable vertically, said means comprising a rack bar extending along saidcolumn, a pinion carried by the table and in mesh with the said rack.bar, anti-friction means for supporting the lower end of said rack bar,said rack bar bei'ng freely removable in an upward direction, saidanti-friction means being arranged around the said column, and meanssecured to the column for supporting said anti-friction means.

4. In a machine tool having a relatively sta-, tionary column and atable supported thereby, means attached to the table and rotatable onthe column for adjusting said table vertically, said means comprising asliding collar embracing the column and extending therealong and meansfor adjusting said table vertically, said adjustingmeans comprising arack bar which extends along the column and whose length is at leastthree times the vertical height of the said collar, a pinion carried bysaid table and in mesh with said rack bar, anti-friction means forsupporting the 7 lower end of said rack bar, said anti-frictionremovable from the machine in an upward di- 5 rectlon.

- HERBERT E. TAUTZ.

